On 2021/1/23 下午4:08, Dongli Zhang wrote:
The size of 'struct vhost_scsi' is order-10 (~2.3MB). It may take long time delay by kzalloc() to compact memory pages by retrying multiple times when there is a lack of high-order pages. As a result, there is latency to create a VM (with vhost-scsi) or to hotadd vhost-scsi-based storage. The prior commit 595cb754983d ("vhost/scsi: use vmalloc for order-10 allocation") prefers to fallback only when really needed, while this patch allocates with kvzalloc() with __GFP_NORETRY implicitly set to avoid retrying memory pages compact for multiple times. The __GFP_NORETRY is implicitly set if the size to allocate is more than PAGE_SZIE and when __GFP_RETRY_MAYFAIL is not explicitly set. Cc: Aruna Ramakrishna <aruna.ramakris...@oracle.com> Cc: Joe Jin <joe....@oracle.com> Signed-off-by: Dongli Zhang <dongli.zh...@oracle.com> --- Changed since v1: - To combine kzalloc() and vzalloc() as kvzalloc() (suggested by Jason Wang) drivers/vhost/scsi.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 4ce9f00ae10e..5de21ad4bd05 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -1814,12 +1814,9 @@ static int vhost_scsi_open(struct inode *inode, struct file *f) struct vhost_virtqueue **vqs; int r = -ENOMEM, i;- vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);- if (!vs) { - vs = vzalloc(sizeof(*vs)); - if (!vs) - goto err_vs; - } + vs = kvzalloc(sizeof(*vs), GFP_KERNEL); + if (!vs) + goto err_vs;vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);if (!vqs)
Acked-by: Jason Wang <jasow...@redhat.com>
